Hymenoptera 



An order of insects which includes the bees, ants, wasps, 

 and ichneumon flies. 



Hyperdispersion 



A pattern of distribution of individuals of a species in an 

 area which is characterized by clumping, or the occurrence 

 of denser aggregations in some spots than in others. Syn. 

 Contagious distribution, Over-dispersion, cf. Hypodispersion, 

 Normal dispersion. 



Hyperparasite 



An organism that is parasitic upon another Parasite. 



Hyperplasy (Hyperplasia) 



An abnormal increase in the number of cells in an 

 organism, e.g., certain plant galls, tumors in animals. 



Hypertrophy 



Usually used to mean an abnormal enlargement, in re- 

 spect to an organism it may include both enlargement of cells 

 and Hyperplasy (q. v.). 



Hypha 



A filament or thread-like structure of a Fungus. 



Hyphal 



Refers to a Hypha. 



Hypocotyl 



The portion of a seed or a seedling between the attach- 

 ment of the Cotyledons and the Radicle. 



Hypodermis 



The layer of cells adjacent to the epidermis in certain 

 plants, in some species the cells are thick-walled, in others 

 used for water storage. 



Hypodispersion 



A pattern of distribution of individuals of a species in 



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